A typical electrical submersible pumping unit consists of an electric motor, a seal section, a multistage centrifugal pump having an appropriate intake section, a round and/or flat power cable, a motor lead extension, a motor controller and a power transformer. In addition to the basic equipment, depending on the application, several accessories may be required, such as tubing joints and couplings, swage nipples, cable guards, clamps, reels and supports, a check valve, a drain valve, centralizers, down hole pressure and temperature sending instrumentation systems, etc.
The equipment, basic as well as accessories, is available in various sizes and types to meet different application requirements. Variables include casing size, production rate, total lift, available power supply and environmental and safety regulation. The equipment can be modified, assembled and installed in different ways giving rise to different configurations/installations for various applications.
In one configuration, a unit is set in or below a perforation zone. Motor cooling is achieved by surrounding the motor housing with a shroud or motor jacket up to just above the pump intake. The motor jacket can be either open ended or packed off using a stinger. The length of the shroud is such as to completely cover the pump intake, seal section and motor. The produced fluid in this case is directed from the perforations downwards along an outer diameter of the shroud. The fluid is further routed to the pump intake through an annular space between a motor outer diameter and a shroud inner diameter. The motor shroud is often selected in applications to either increase fluid velocity past the motor for cooling purposes, or as a gas separator when placed below the perforations. The gas separation process uses the natural buoyancy of the fluid for separation. It is also possible to invert the shroud and install the unit above the perforations wherein the shroud is used as a gas separator.
Common practice for affixing the motor shroud to the electrical submersible pump assembly is to bolt the shroud onto the pump while the pump assembly is hanging from the rig. Next, a split ring is bolted to the shroud to seal off the upper portion of the shroud. This procedure requires precise alignment of the pump assembly and motor shroud, as well as dexterity to thread in the bolts. Further, this process can be difficult to implement with gloved hands. Bolts can accidentally be dropped down the hole. Therefore, it is desirable to provide a method and apparatus for facilitating ease of installation and removal of a motor shroud on an electrical submersible pump assembly.